新型量子点修饰分子灯塔探针及其作为DNA传感器应用

Preparation of a novel molecular beacon and its application as DNA biosensor

以CdTe量子点为能量供体，BHQ-1为能量受体构建了一种基于能量共振转移原理（FRET）的分子灯塔探针。能量供体与受体分别连接于分子灯塔探针DNA链的两端，由于探针的自杂交作用可将能量供体与受体之间的距离控制在1～10nm之间，并且供体的荧光发射光谱与受体的紫外吸收光谱存在一定程度的重叠，因此满足FRET原理。此探针体系可以作为DNA传感器较好的区分与探针碱基序列完全匹配的DNA、单碱基错配的DNA、完全不匹配的DNA。

A novel molecular beacons （MBs） system based on fluorescence resonance energy transfer （FRET） from CdTe quantum dots （QDs） donors to the Black Hole QuencherTM dyes （BHQ-1） as energy acceptor is designed. CdTe QDs as energy donors are prepared in water and linked to 5＇-NH2-DNA-BHQ-1 when 1-ethyl-3-（dimethylaminopropyl） carbodi-imide hydrochloride （EDC） exists. The self-hybridization exists in the stem part of probe DNA because the base pairs of the stem part are complementary, and this results in the FRET process occurring between acceptor and donor because the energy acceptor and donor are close enough just about 1 - 10 run and the emission spectra of donors and the absorption spectra of acceptors have a certain degree of overlap. The DNA detection results indicate that this DNA biosensors system can distinguish complementary target DNA, a mismatching base-pair DNA and non-complementary DNA sequence.